  (function(win, doc) {
      let startBtn = doc.querySelector("#startBtn");
      let timer;
      let names = ["程瑞峰", "迟明旭", "邓霜楠", "邓岩松", "杜晓祺", "冯密玺", "高然", "高腾", "高俊俊", "公维斌", "谷志颖", "胡文文", "胡晓峰", "贾方赫", "贾霖霖", "贾志杰", "姜久铭", "李宇", "李聪聪", "李飞扬", "李佳霖", "刘佳鑫", "刘雨晨", "吕晓莎", "马克", "马浩然", "米佳妮", "曲 琪", "唐宇", "田源", "王强", "王卫东", "王文澳", "王治国", "奚天洋", "徐雍胜", "许苗苗", "闫霖", "于鑫尧", "张鑫", "张春雷", "张席伟", "郅晓雄"];
      let cont = document.querySelector("#cont");
      //入口函数
      var init = function() {
              initEvent()
          }
          //事件函数
      var initEvent = function() {
              startBtn.onclick = start;
              stopBtn.onclick = stop;
          }
          //开始事件
      var start = function() {
              if (timer) {
                  clearInterval(timer)
              }
              timer = setInterval(function() {
                  let num = Math.floor(Math.random() * names.length);
                  cont.innerHTML = names[num]
              }, 100)
          }
          //停止事件
      var stop = function() {
          clearInterval(timer)
      }
      init()

  })(window, document)